The objective of this project is to define and interrelate the biological factors, particularly the influence of genetics, on reproductive function in felid species. Emphasis is placed on gamete interaction and embryo maturation in vitro and in vivo. Findings are relevant to (1) fundamental studies of fertilization mechanisms, (2) the propagation of genetically valuable laboratory animals and endangered species, and (3) developmental studies which eventually will allow delivering molecularly cloned genes into early-staged preimplantation embryos. Areas of effort primarily focus on (1) in vitro fertilization and embryo development in vitro and in vivo; (2) artificial insemination via laparoscopic deposition of spermatozoa; and (3) oocyte rescue, maturation in vitro and the development of gene delivery techniques into embryos which will allow studying the mechanisms associated with transformation and inborn errors in early development. Current emphasis is applied to the gametes and embryos of the domestic cat with comparative studies conducted in a variety of nondomesticated Felidae species. Progress to date has allowed (1) the routine production of embryos in domestic and nondomestic cats by in vitro fertilization; (2) the routine culture of embryos to the morula stage in vitro; (3) determining the biological competence of in vitro produced embryos from both domestic and nondomestic felid species; (4) the successful development of an efficient transabdominal artificial insemination approach; (5) in vitro maturation of immature, antral oocytes from both domestic and nondomestic felid species and the fertilization and development of these oocytes in vitro; and (6) the discovery that the oocytes of various felid species have no mechanism for excluding penetration by heterologous or "foreign" spermatozoa.